Quantifying vascular health


Oxygen fuels the body and enables it to maintain and replace billions of cells every day.


Tissue integrity is dependent on a healthy vascular system delivering sufficient oxygen to the capillary network. Common chronic diseases (like diabetes and peripheral vascular disease) or certain lifestyle choices (like smoking) can cause subtle changes throughout the vascular network, impacting perfusion and tissue oxygen delivery. Combined with microvascular regulation dysfunction — due to neuropathy — the results can be devastating.



These changes to the microvascular system are difficult to detect — but vitally important when making diagnostic and treatment decisions. This is especially true for patients with compromised circulation.


For clinicians, the ability to objectively quantify vascular health can be the difference between life and death for their patients.

Case study: Compromised circulation in patients with diabetes


Lower extremity complications — especially ulcers — are a major sequela of diabetes. Despite treatment advances in recent years, diabetic foot complications, including infections, ulcerations and amputations, are still common, costly, and debilitating. This is bad for patients, providers, and payers.


Consider the following startling facts about one of the most serious complications of diabetes:


Studies show that at least 75% of DFUs are preventable if clinicians identify at-risk patients early and elevate them into appropriate treatment pathways (Boulton et al., 2008). Preventing DFUs before they actually occur can help save limbs, lives, and billions of dollars in treatment costs. The problem is that conventional assessment methods are lacking.

Physical assessment, including a lower extremity physical exam, is the primary method of screening for DFUs, followed by such tests as monofilament, ankle-brachial index (ABI) and toe-brachial index (TBI). None of these conventional point-of-care methods gets at the underlying cause of DFUs: compromised microcirculation due to onset of neuropathy and peripheral arterial disease (PAD).


  • Vascular assessment: PAD is a major co-morbidity in approximately 1/3 of DFUs —and is a significant risk factor for recurrent ulcers (Marso & Hiatt, 2006). Despite the critical need to identify PAD in diabetics, the most common vascular test (ABI) is often misleading in patients with diabetes, due to the confounding effect of arteriosclerosis (Al-Qaisi et al., 2009; Boulton et al., 2008).
  • Neurological assessment: Diabetic peripheral neuropathy is a critical component of DFU etiology. Unfortunately, the current monofilament test is designed to identify loss of protective sensation (LOPS) rather than autonomic circulation loss and its results are also subjective.
  • Dermatologic assessment: Differences in skin temperature, texture, and hair growth between feet may be predictive of vascular disease or potential ulceration, but they are highly inaccurate and subjective.


These assessment methods and tools are subjective, inaccurate, time-consuming, and not repeatable. Because of these limitations, clinicians lack confidence in others’ results, leading to unnecessary repeat testing. Late indicators at best, they are gross assessments with no local quantification of tissue perfusion and oxygenation.

There needs to be a better way


Clinicians need a more dependable tool for identifying the underlying conditions and early signs of a DFU while there is still time to intervene and prevent ulceration. Such a tool could also help clinicians monitor progress and assess patient response to treatment. The tool would help clinicians to risk-stratify patients, target interventions where they’re most needed, and improve patients’ chances of survival.


Modulim’s goal is to develop technology that helps clinicians prevent the onset or escalation of diabetic foot ulcers — and other complications of vascular compromise. Ideally, we want to help prevent an ulcer from occurring in the first place, so we have honed our solution around early detection. In the event that an ulcer has already occurred, we want to provide a tool to help prevent worsening and subsequent ulcers.